INDETERMINATE
FORM
By
SHIVAM SHARMA
BWU/BTS/20/122
CONTENTS:-
2
▹ HISTORY
▹ DEFINITION
▹ TYPES OF INDETERMINATE FORMS
▹ L-HOSPITAL’S RULE
▹ LIST OF COMMON INDETERMINATE FORMS
3
-HISTORY-
The term was originally
introduced by Cauchy's
student Moigno (also known as
François-Napoléon-Marie Moigno)
in the middle of the 19th century.
INDETERMINATE FORMS
 What are indeterminate forms?
In calculus and other branches of mathematical
analysis, limits involving an algebraic combination of
functions in an independent variable may often be
evaluated by replacing these functions by their limits.
If the expression obtained after this substitution does
not give enough information to determine the original
limit, it is said to take on an indeterminate form.
4
TYPES OF
INDETERMINATE
FORMS
5
6
Types of indeterminate forms
 There are seven types of indeterminate forms:
0
0
0
0
0
0
1


 
  

1.
2.
3.
4.
5.
6.
7.
L-HOSPITAL’S RULE
7
L’Hospital's rule is a general
method for evaluating the
indeterminate forms 0/0 &
∞/∞. This rule states that…
(under appropriate
conditions)
( ) '( )
( ) '( )
x c x c
f x f x
g x g x
lim lim
 

*where f’(x)and g’(x) are thederivatives of f(x) and g(x).
8
0
:
0
Rulestoevaluate form
1. Check whether the limit is an indeterminate form. If it is not, then
we cannot apply L’ Hospital's rule.
2. Differentiate f(x) and g(x) separately.
3. If g’(a) ≠ 0, then the limit will exist. It may be finite, +∞ or -∞. If
g’(a)=0 then follow rule 4.
4. Differentiate f’(x) & g’(x) separately.
5. Continue the process till required value is reached.
“
▹ In this form you can
directly apply the L-
HOSPITAL’S RULE in the
equation.
0
1.
0
form
9
( ) '( )
( ) '( )
x c x c
f x f x
g x g x
lim lim
 

_____________________________________________
“
▹ Same as the previous one,
you can directly apply the L-
Hospital’s rule in the
equation.
10
2. form


( ) '( )
( ) '( )
x c x c
f x f x
g x g x
lim lim
 

_____________________________________________
11
Example
0
0
form form


5 2
lim
7 3
x
x
Find
x



Solution:
5 2
lim
7 3
5 2
lim
7 3
5 2
lim
7 3
x
x
x
x
form
x
x
x
x
x
x
x x
x
x x



 
 
   
 
 






2
5
lim
3
7
5 0
7 0
5
7
x
x
x








“
12
3. 0 form

 Limit of the form
are called indeterminate form of the
type.
 If we write f(x) g(x) = f(x) / [1/g(x)], then
the limit becomes of the form .
 Therefore, this can be evaluated by
using L-Hospital’s rule.
lim ( ) 0,lim ( )
x c x c
f x g x
 
  
0
0
0
_____________________________________________
13
Example
2
lim sin .
x
Consider x
x

 
 
  
 
 
 
2
sin
lim
1
x
x
x

 
 
 
 
 
 

 
 
 
   
2
2
2
sin
lim
1
2 2
cos
lim
1
2
lim 2cos
2cos 2 2cos 0 2
x
x
x
x
x
x x
x
x



 
 
 
 
 
 

 
 
 
  

  
  


 
  
 
   
Solution:
 First flip the x to denominator
*Now this limit has the form of 0/0. (We have simply
taken the ∞, and transformed it into a 0
In the denominator.) Therefore, this limit can be
done with L-Hospital’s rule.
“
14
4. form
 
 Limit of the form
are called indeterminate form of the
type.
 If we write
then, the limit becomes of the form 0/0
and can be evaluated by using the L-
---Hospital’s rule.
lim ( ) ,lim ( )
x c x c
f x g x
 
   
  
1 ( ) 1 ( )
lim( ( ) ( )) lim
1 ( ( ) ( ))
x c x c
g x f x
f x g x
f x g x
 

 
_____________________________________________
15
Example
“
16
0
5. 0 form
 Limit of the form
are called indeterminate form of the
type.
 If we write
then, the limit becomes of the form 0/0
and can be evaluated by using the L-
---Hospital’s rule.
lim ( ) 0 ,lim ( ) 0
x c x c
f x g x

 
 
( ) ( )
lim ( ) explim
1 ln ( )
g x
x c x c
g x
f x
f x
 

_____________________________________________
0
0
17
Example
0
lim .
x
x
Find x


Solution:
This is an indeterminate form of the type
Let
0
0
ln ln ln
x x
y x y x x x
   
2
0 0 0 0
0
0
ln 1
lim ln lim lim lim( ) 0.
1 1
, lim 1
x x x x
x
x
x x
y x
x x
Thus x e
   

   

     

 
“
18
6. 1 form

 Limit of the form
are called indeterminate form of the
type.
 If we write
then, the limit becomes of the form 0/0
and can be evaluated by using the L-
---Hospital’s rule.
lim ( ) 1,lim ( )
x c x c
f x g x
 
  
( ) ( )
lim ( ) explim
1 ( )
g x
x c x c
f x
f x
g x
 

_____________________________________________
1
19
Example
1
0
lim (cos )x
x
Find x


Solution:
This is an indeterminate form of the type
Let
1
1
(cos )x
y x

 
 
1
0 0 0
1
0
0
ln(cos )
ln ln cos
ln(cos )
lim ln lim lim( tan ) 0.
, lim cos 1.
x
x x x
x
x
x
y x
x
x
y x
x
Thus x e
  

  

 
  
 
 
    
 
“
20
 Limit of the form
are called indeterminate form of the
type.
 If we write
then, the limit becomes of the form 0/0
and can be evaluated by using the L-
---Hospital’s rule.
lim ( ) ,lim ( ) 0
x c x c
f x g x
 
  
_____________________________________________
0
7. form

0

( ) ( )
lim ( ) explim
1 ( )
g x
x c x c
f x
f x
g x
 

21
Example
2
lim( 1)
x x
x
Find e



Solution:
This is an indeterminate form of the type
Let
 
2
2
2
2ln( 1)
ln ln ( 1)
2
2
1
2ln( 1)
limln lim lim lim 2
1
,lim( 1) .
x
x x
x
x
x
x
x
x x x x
x x
x
e
y e
x
e
e
e
e
y
x e
Thus e e

   



   
   
 
 
 
   

   
     
 
0

2
( 1)
x x
y e

 
22
 The following table lists the most common indeterminate forms, and the transformations for applying l'Hôpital's rule.
23
THANKS !!
We have reached the end of the presentation.!!!

Indeterminate form

  • 1.
  • 2.
    CONTENTS:- 2 ▹ HISTORY ▹ DEFINITION ▹TYPES OF INDETERMINATE FORMS ▹ L-HOSPITAL’S RULE ▹ LIST OF COMMON INDETERMINATE FORMS
  • 3.
    3 -HISTORY- The term wasoriginally introduced by Cauchy's student Moigno (also known as François-Napoléon-Marie Moigno) in the middle of the 19th century.
  • 4.
    INDETERMINATE FORMS  Whatare indeterminate forms? In calculus and other branches of mathematical analysis, limits involving an algebraic combination of functions in an independent variable may often be evaluated by replacing these functions by their limits. If the expression obtained after this substitution does not give enough information to determine the original limit, it is said to take on an indeterminate form. 4
  • 5.
  • 6.
    6 Types of indeterminateforms  There are seven types of indeterminate forms: 0 0 0 0 0 0 1         1. 2. 3. 4. 5. 6. 7.
  • 7.
    L-HOSPITAL’S RULE 7 L’Hospital's ruleis a general method for evaluating the indeterminate forms 0/0 & ∞/∞. This rule states that… (under appropriate conditions) ( ) '( ) ( ) '( ) x c x c f x f x g x g x lim lim    *where f’(x)and g’(x) are thederivatives of f(x) and g(x).
  • 8.
    8 0 : 0 Rulestoevaluate form 1. Checkwhether the limit is an indeterminate form. If it is not, then we cannot apply L’ Hospital's rule. 2. Differentiate f(x) and g(x) separately. 3. If g’(a) ≠ 0, then the limit will exist. It may be finite, +∞ or -∞. If g’(a)=0 then follow rule 4. 4. Differentiate f’(x) & g’(x) separately. 5. Continue the process till required value is reached.
  • 9.
    “ ▹ In thisform you can directly apply the L- HOSPITAL’S RULE in the equation. 0 1. 0 form 9 ( ) '( ) ( ) '( ) x c x c f x f x g x g x lim lim    _____________________________________________
  • 10.
    “ ▹ Same asthe previous one, you can directly apply the L- Hospital’s rule in the equation. 10 2. form   ( ) '( ) ( ) '( ) x c x c f x f x g x g x lim lim    _____________________________________________
  • 11.
    11 Example 0 0 form form   5 2 lim 73 x x Find x    Solution: 5 2 lim 7 3 5 2 lim 7 3 5 2 lim 7 3 x x x x form x x x x x x x x x x x                      2 5 lim 3 7 5 0 7 0 5 7 x x x        
  • 12.
    “ 12 3. 0 form  Limit of the form are called indeterminate form of the type.  If we write f(x) g(x) = f(x) / [1/g(x)], then the limit becomes of the form .  Therefore, this can be evaluated by using L-Hospital’s rule. lim ( ) 0,lim ( ) x c x c f x g x      0 0 0 _____________________________________________
  • 13.
    13 Example 2 lim sin . x Considerx x               2 sin lim 1 x x x                         2 2 2 sin lim 1 2 2 cos lim 1 2 lim 2cos 2cos 2 2cos 0 2 x x x x x x x x x                                              Solution:  First flip the x to denominator *Now this limit has the form of 0/0. (We have simply taken the ∞, and transformed it into a 0 In the denominator.) Therefore, this limit can be done with L-Hospital’s rule.
  • 14.
    “ 14 4. form   Limit of the form are called indeterminate form of the type.  If we write then, the limit becomes of the form 0/0 and can be evaluated by using the L- ---Hospital’s rule. lim ( ) ,lim ( ) x c x c f x g x          1 ( ) 1 ( ) lim( ( ) ( )) lim 1 ( ( ) ( )) x c x c g x f x f x g x f x g x      _____________________________________________
  • 15.
  • 16.
    “ 16 0 5. 0 form Limit of the form are called indeterminate form of the type.  If we write then, the limit becomes of the form 0/0 and can be evaluated by using the L- ---Hospital’s rule. lim ( ) 0 ,lim ( ) 0 x c x c f x g x      ( ) ( ) lim ( ) explim 1 ln ( ) g x x c x c g x f x f x    _____________________________________________ 0 0
  • 17.
    17 Example 0 lim . x x Find x   Solution: Thisis an indeterminate form of the type Let 0 0 ln ln ln x x y x y x x x     2 0 0 0 0 0 0 ln 1 lim ln lim lim lim( ) 0. 1 1 , lim 1 x x x x x x x x y x x x Thus x e                   
  • 18.
    “ 18 6. 1 form  Limit of the form are called indeterminate form of the type.  If we write then, the limit becomes of the form 0/0 and can be evaluated by using the L- ---Hospital’s rule. lim ( ) 1,lim ( ) x c x c f x g x      ( ) ( ) lim ( ) explim 1 ( ) g x x c x c f x f x g x    _____________________________________________ 1
  • 19.
    19 Example 1 0 lim (cos )x x Findx   Solution: This is an indeterminate form of the type Let 1 1 (cos )x y x      1 0 0 0 1 0 0 ln(cos ) ln ln cos ln(cos ) lim ln lim lim( tan ) 0. , lim cos 1. x x x x x x x y x x x y x x Thus x e                        
  • 20.
    “ 20  Limit ofthe form are called indeterminate form of the type.  If we write then, the limit becomes of the form 0/0 and can be evaluated by using the L- ---Hospital’s rule. lim ( ) ,lim ( ) 0 x c x c f x g x      _____________________________________________ 0 7. form  0  ( ) ( ) lim ( ) explim 1 ( ) g x x c x c f x f x g x   
  • 21.
    21 Example 2 lim( 1) x x x Finde    Solution: This is an indeterminate form of the type Let   2 2 2 2ln( 1) ln ln ( 1) 2 2 1 2ln( 1) limln lim lim lim 2 1 ,lim( 1) . x x x x x x x x x x x x x x x e y e x e e e e y x e Thus e e                                        0  2 ( 1) x x y e   
  • 22.
    22  The followingtable lists the most common indeterminate forms, and the transformations for applying l'Hôpital's rule.
  • 23.
    23 THANKS !! We havereached the end of the presentation.!!!